JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
    <div class="item">Item 1</div>
    <div class="item">Item 2</div>
    <div class="item">Item 3</div>
    <div class="item fixed">Fixed Item</div>
</div>

CSS

html, body {
    min-height: 100%;
    height: 100%;
}

.container {
    height: 50%;
    background: #EEE;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    align-content: center;
}

.item {
    background: #CCC;
}

.fixed {
    align-self: flex-end;
}